Method for producing a bio-fuel

ABSTRACT

A method for producing a bio-fuel may include selecting a first and a second plant species such that the second plant species, when grown together in competition with the first plant species, causes a BTU value of the first plant species to increase above a range of BTU values that the first plant species has when grown alone. The method may further include planting a combination of the first and second plant species together in competition, harvesting the combination of the first and second plant species when sufficiently mature, and processing the harvested combination of the first and second plant species to produce the bio-fuel.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to Provisional Patent Application Ser. No. 60/982,044, filed Oct. 23, 2007, the disclosure of which is incorporated herein by reference,

FIELD OF THE INVENTION

The present invention relates generally to methods for producing a bio-fuel, and more specifically to methods for producing a biomass that forms the bio-fuel or from which the bio-fuel may be derived.

BACKGROUND

Agricultural plants are known to have various physical characteristics and properties. It is desirable to select and plant one or more plant species in a manner that achieves one or more desired bio-fuel production and/or performance goals.

SUMMARY

The present invention may comprise one or more of the features recited in the attached claims, and/or one or more of the following features and combinations thereof. A method for producing a bio-fuel may comprise selecting a first and a second plant species such that the second plant species, when grown together in competition with the first plant species, causes a BTU value of the first plant species to increase above a range of BTU values that the first plant species has when grown alone, planting a combination of the first and second plant species together in competition, harvesting the combination of the first and second plant species when sufficiently mature, and processing the harvested combination of the first and second plant species to produce the bio-fuel.

The first plant species may have a lignin content. The second plant species may cause the BTU value of the first plant species to increase by causing the first plant species to grow with greater lignin content than when grown alone. The lignin content of the first plant species varies as a function of a size of the first plant species. The second plant species may be a catalytic plant species that, when grown together in competition with the first plant species, causes the first plant species to grow larger than when grown alone so that the lignin content of the first plant species correspondingly increases. The first plant species may be ambrosia trifida. The second plant species may be a tall-growing, high-lignin one or a combination of a corn species and a sorghum species. For example, the second plant species may be one or a combination of a G family, an E series and a tropical corn series hybrid corn species and a number 1506 hybrid sorghum species. Planting a combination of the first and second plant species may further comprise planting ambrosia artemisiifolia along with the first and second plant species such that a resulting combination comprises ambrosia trifida, a tall-growing, high-lignin one or a combination of a corn species and a sorghum species and ambrosia artemisiifolia. Harvesting may comprise harvesting the resulting combination when sufficiently mature. The method may further comprise carrying out the selecting, the planting and the harvesting events at least twice in a single growing season. The second plant species for a first one of the selecting, the growing and the harvesting events may be the tall-growing, high-lignin corn species. The second plant species for a second one of the selecting, the growing and the harvesting events may be the tall-growing, high-lignin sorghum species.

The method may further comprise selecting the second plant species to have a BTU value that is within a predefined range of BTU values. The predefined range of BTU values may be greater than or equal to the range of BTU values of the first plant species.

The method may further comprise selecting either of the first and second plant species to have resistance to root pests.

The method may further comprise selecting either of the first and second plant species to have resistance to corn borer insects and/or to stalk-boring insects.

Harvesting may comprise cutting the combination of the first and second plant species at a predetermined height above the ground. The predetermined height may be selected to minimize dirt spatter and/or silicon dioxide on the cut combination of the first and second plant species. Harvesting further comprises reducing the cut combination of the first and second plant species to smaller pieces.

Planting a combination of the first and second plant species may further comprise planting a third plant species along with the first and second plant species such that a resulting combination comprises the first, second and third plant species. The third plant species may be selected to at least temporarily supplement one of the first and second plant species. Harvesting may comprise harvesting the resulting combination when sufficiently mature. Harvesting may further comprise cutting the resulting combination of the first, second plant and third species at a predetermined height above the ground. The predetermined height may be selected to minimize dirt spatter and/or silicon dioxide on the cut combination of the first, second and third plant species. Harvesting may further comprise reducing the cut combination of the first, second and third plant species to smaller pieces.

Processing may comprise processing the harvested combination to produce the bio-fuel in any of a solid, a powder and a pellet form. Alternatively or additionally, processing may comprise processing the harvested combination to produce a bio-mass, and processing the bio-mass to produce any of ethanol, bio-diesel fuel, bio-gas, bio-oil, solid bio-fuel, powder bio-fuel and pelletized bio-fuel.

A method for producing a bio-fuel may comprise selecting a first and a second plant species such that the second plant species, when grown together in competition with the first plant species, causes the first plant species to grow larger, so that the first plant species produces a greater yield, than when grown alone, planting a combination of the first and second plant species together in competition, harvesting the combination of the first and second plant species when sufficiently mature, and processing the harvested combination of the first and second plant species to produce the bio-fuel.

The first and second plant species may be selected such that the second plant species, when grown together in competition with the first plant species, causes the first plant species to grow taller than when grown alone. The first plant species may be ambrosia trifida. The second plant species may be a tall-growing, high-lignin one or a combination of a corn species and a sorghum species. For example, the second plant species may be one or a combination of a G family, an E series and a tropical corn series hybrid corn species and a number 1506 hybrid sorghum species. Planting a combination of the first and second plant species may further comprise planting ambrosia artemisiifolia along with the first and second plant species such that a resulting combination comprises ambrosia trifida, a tall-growing, high-lignin one or a combination of a corn species and a sorghum species and ambrosia artemisiifolia. Harvesting may comprise harvesting the resulting combination when sufficiently mature. The method may further comprise carrying out the selecting, the planting and the harvesting events twice in a single growing season. The second plant species for a first one of the selecting, the growing and the harvesting events may be the tall-growing, high-lignin corn species. The second plant species for a second one of the selecting, the growing and the harvesting events may be the tall-growing, high-lignin sorghum species.

The first and second plant species may be selected such that the second plant species, when grown together in competition with the first plant species, causes the first plant species to grow larger by growing generally the same height but with greater weight than when grown alone.

The first plant species may further be selected to have a BTU value that is within a first range of BTU values. The second plant species may further be selected to have a BTU value that is within a second range of BTU values. The second range of BTU values may be greater than or equal to the first range of BTU values. The first and second plant species may further be selected such that, when grown together, the second plant species causes the first plant species to have a BTU value that is greater than the first range of BTU values.

The second plant species may further be selected such that, when grown together in competition with the first plant species, the second plant species also grows larger than when grown alone so that the combination of the first plant species produces a greater yield than when grown alone,

The method may further comprise selecting either of the first and second plant species to have resistance to root pests.

Alternatively or additionally, the method may further comprise selecting either or both of the first and second plant species to have resistance to corn borer insects and/or to stalk-boring insects.

Harvesting may comprise cutting the combination of the first and second plant species at a predetermined height above the ground. The predetermined height may be selected to minimize dirt spatter and/or silicon dioxide on the cut combination of the first and second plant species. Harvesting may further comprise reducing the cut combination of the first and second plant species to smaller pieces.

Planting a combination of the first and second plant species may further comprise planting a third plant species along with the first and second plant species such that a resulting combination comprises the first, second and third plant species. The third plant species may be selected to at least temporarily supplement one of the first and second plant species. Harvesting may comprise harvesting the resulting combination when sufficiently mature.

Harvesting may comprise cutting the resulting combination of the first, second plant and third species at a predetermined height above the ground. The predetermined height may be selected to minimize dirt spatter and/or silicon dioxide on the cut combination of the first, second and third plant species. Harvesting may further comprise reducing the cut combination of the first, second and third plant species to smaller pieces.

Processing may comprise processing the harvested combination to produce the bio-fuel in any of a solid, a powder and a pellet form. Alternatively or additionally, processing may comprise processing the harvested combination to produce a bio-mass, and processing the bio-mass to produce any of ethanol, bio-diesel fuel, bio-gas, bio-oil, solid bio-fuel, powder bio-fuel and pelletized bio-fuel.

A method for producing a bio-fuel may comprise planting a species of Amaranthus on one or more parcels of land, mixing additional phosphorus with a base fertilizer to form a modified fertilizer, fertilizing the planted Amaranthus with the modified fertilizer, harvesting the fertilized Amaranthus when sufficiently mature, and processing the harvested Amaranthus to produce the bio-fuel.

The base fertilizer may be a nitrogen-phosphorus-potassium fertilizer.

Planting a species of Amaranthus may comprise planting Amaranthus rudis. Alternatively or additionally, planting a species of Amaranthus may comprise planting Amaranthus hybridus. Alternatively or additionally, planting a species of Amaranthus may comprise planting Amaranthus retroflexus.

The method may further comprise carrying out the planting, mixing, fertilizing and harvesting events at least twice in a single growing season.

The method may further comprise carrying out the mixing, fertilizing and harvesting events at least twice in a single growing season.

Harvesting may comprise cutting the species of amaranthus at a predetermined height above the ground. The predetermined height may be selected to minimize at least one of dirt spatter and silicon dioxide on the cut species of Amaranthus. Harvesting may further comprise reducing the cut species of Amaranthus to smaller pieces.

Processing may comprise processing the harvested species of Amaranthus to produce the bio-fuel in any of a solid, a powder and a pellet form. Alternatively or additionally, processing may comprise processing the harvested species of Amaranthus to produce a bio-mass, and processing the bio-mass to produce any of ethanol, bio-diesel fuel, bio-gas, bio-oil, solid bio-fuel, powdered bio-fuel and pelletized bio-fuel.

A method for producing a bio-fuel may comprise planting a first plant species on a first parcel of land, planting a second plant species on a second parcel of land, harvesting the first plant species when sufficiently mature, harvesting the second plant species when sufficiently mature, and processing a combination of the harvested first and second plant species to produce the bio-fuel.

The method may further comprise mixing additional phosphorus with a base fertilizer to form a modified fertilizer, and fertilizing at least one of the planted first plant species and the planted second plant species with the modified fertilizer. The base fertilizer may be a nitrogen-phosphorus-potassium fertilizer.

Harvesting may comprise cutting each of the first plant species and the second plant species at a predetermined height above the ground. The predetermined height may be selected to minimize at least one of dirt spatter and silicon dioxide on the cut first and second plant species.

Harvesting may further comprise reducing the cut first plant species to smaller pieces and reducing the cut second plant species to smaller pieces.

Processing may comprise processing the harvested first and second plant species to produce the bio-fuel in any of a solid, a powder and a pellet form. Alternatively or additionally, processing may comprise processing the harvested first and second plant species to produce a bio-mass, and processing the bio-mass to produce any of ethanol, bio-diesel fuel, bio-gas, bio-oil, solid bio-fuel, powdered bio-fuel and pelletized bio-fuel.

The method may further comprise planting a third plant species on a third parcel of land, and harvesting the third plant species when sufficiently mature. Processing may comprise processing a combination of the harvested first, second and third plant species to produce the bio-fuel. The first plant species may comprises at least one of Amaranthus rudis, Amaranthus hybrid us and Amaranthus retroflexus, the second plant species may comprise at least one of Ambrosia trifida and Ambrosia artemisiifolia, and the third plant species may comprise at least one of a corn species and a sorghum species.

In any of the embodiments including at least first and second plant species, the first plant species may comprise at least one of Amaranthus rudis, Amaranthus hybridus and Amaranthus retroflexus, and the second plant species may comprise at least one of Ambrosia trifida and Ambrosia artemisiifolia. Alternatively, the first plant species may comprise at least one of Ambrosia trifida and Ambrosia artemisiifolia, and the second plant species may comprise at least one of Amaranthus rudis, Amaranthus hybridus and Amaranthus retroflexus. Alternatively still, the first plant species may comprise at least one of Amaranthus rudis, Amaranthus hybridus and Amaranthus retroflexus, and the second plant species may comprise at least one of a corn species and a sorghum species. Alternatively still, the first plant species may comprise at least one of Ambrosia trifida and Ambrosia artemisiifolia, and the second plant species may comprise at least one of a corn species and a sorghum species.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flowchart of one illustrative process for producing a bio-fuel.

FIG. 2 is a flowchart of one illustrative embodiment of the harvesting event of the process illustrated in FIG. 1.

FIG. 3 is a flowchart of another illustrative process for producing a bio-fuel.

FIG. 4 is a flowchart of another illustrative process for producing a bio-fuel.

DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENTS

For the purposes of promoting an understanding of the principles of the invention, reference will now be made to a number of illustrative embodiments shown in the attached drawings and specific language will be used to describe the same.

Referring now to FIG. 1, a flowchart of one illustrative process 100 for producing a bio-fuel is shown. For purposes of this disclosure, the term bio-fuel is defined as a solid, liquid or gas fuel consisting of, or derived from, biomass, wherein the term biomass is defined as plant and/or animal matter and/or biodegradable waste that can be burnt as fuel.

The process 100 begins at step 102 where first and second plant species are selected which, when grown together in competition, achieve one or more desired bio-fuel production and/or performance goals. For purposes of this disclosure, first and second plant species are “grown together in competition” by being grown interspersed with each other on a common plot of land such that each competes with the other for one or more of the same sunlight, shade, water, fertilizer and the like. One example of a desired bio-fuel production goal is increased yield, i.e., yield of the resulting biomass product, over the yield that would otherwise be achieved by growing the two plant species alone, i.e., separately. Those skilled in the art will recognize other desired bio-fuel production goals, and such other desired bio-fuel production goals are contemplated by this disclosure. One example of a desired bio-fuel performance goal is increased BTU value of the first and/or second plant species over the BTU value otherwise associated with the corresponding first and/or second plant species when grown alone, i.e., separately. Those skilled in the art will recognize other desired bio-fuel performance goals, and such other desired bio-fuel performance goals are contemplated by this disclosure.

It will be understood that the example bio-fuel production and performance goals given above may be achievable together or separately through appropriate selection of plant species. For example, the first and second plant species may be selected such that the second plant species, when grown together in competition with the first plant species, causes a BTU value of the first and/or second plant species to increase above a range of BTU values that the corresponding first and/or second plant species has when grown alone. This may illustratively be accomplished by selecting the first and second plant species such that the second plant species, when grown together in competition with the first plant species, causes the lignin content of the first species to increase above that which it would otherwise be when grown alone. Increasing the lignin content of the first plant species may be accomplished, for example, by selecting the first and second plant species such that the second plant species, when planted together in competition with the first plant species, causes the first plant species to grow larger than when grown alone. For purposes of this disclosure, the phrase “grow larger than when grown alone” means either or both of being grown taller than when grown alone and being grown with stalks/branches having greater girth such that the plant generally grows the same height as when grown alone, but with more weight than when grown along due to the greater girth of the stalks and/or branches. Of course, selecting the first and second plant species such that the second plant species, when planted together in competition with the first plant species, causes the first plant species to grow larger than when grown alone will also achieve the example bio-fuel production goal of increasing the yield of the first plant species and, therefore, the yield of the biomass product. Thus, selecting the first and second plant species such that the second plant species, when planted together in competition with the first plant species, causes the first plant species to have an increased BTU value due to increased lignin as a result of growing larger than when grown alone, achieves both the bio-fuel performance goal of increased BTU value and the bio-fuel production goal of increased yield. It should be understood, however, that selecting the first and second plant species such that the second plant species, when gown together in competition with the first plant species, may increase the BTU value of the first plant species by increasing its lignin content, but need not also cause either plant species to grow larger, or otherwise increase the yield of the resulting biomass product, than when grown alone. Likewise, selecting the first and second plant species such that the second plant species, when gown together in competition with the first plant species, may increase the yield of the biomass product by causing the first and/or second plant species to grow larger than when grown alone, but need not also increase the lignin content, or otherwise increase the BTU value, of either plant species.

The process 100 may include an optional step 104, as shown in phantom in FIG. 1, in which a third plant species is selected that at least temporarily supplements the first and/or second plant species. An example of one such third plant species will be provided hereinafter.

The process 100 may further include another optional step 106 that follows step 102 in embodiments that do not include step 104, and that follows step 104 in embodiments that do include step 104. In any case, at step 106 the first, second and/or third plant species is/are further selected to have one or more specified characteristics. For example, the first, second and/or third plant species may be further selected such that the first, second and/or third plant species and/or resulting biomass product has/have one or more burning characteristics such as limited burn emissions, one or more post-burn ash characteristics, or the like. As another example, the first, second and/or third plant species may be further selected such that the first, second and/or third plant species has/have one or more specified growing characteristics such as drought resistance, resistance to root pests, resistance to insects, e.g., corn bore insects, stalk-boring insects, sunlight/shade preference, water amount/frequency requirements, growth enhancement and/or grown plant property enhancement resulting from one or more specific fertilizer components, and the like. As yet another example, the first, second and/or third plant species may further be selected such that the first, second and/or third plant species and/or resulting biomass product, has/have one or more inherent properties such as BTU value or range of values, burn emissions content, post-burn ash content, e.g., nutrient content, and the like. Those skilled in the art will recognize other criteria for further selecting the first, second and/or third plant species, and any such other plant species selection criteria are contemplated by this disclosure.

From step 102 in embodiments that do not include steps 104 and/or 106, or from either of steps 104 and 106 in embodiments that include these steps, the process 100 advances to step 108. At step 108, the first and second plant species that were selected at step 102, and possibly further at step 106, or the first, second and third plant species that were selected at steps 102 and 104, and possibly further at step 106, are planted together in competition. More specifically, at step 108, the first and second plant species, or alternatively the first, second and third plant species, are planted interspersed together on a common plot of land as described hereinabove. Illustratively, although not specifically illustrated in FIG. 1, the process 100 may include an additional step in which the first and second, or the first, second and third, plant species are fertilized with a selected fertilizer. For example, a base fertilizer may be used in which phosphorus is added to increase the phosphorus content of the base fertilizer. The base fertilizer may be, for example, a conventional nitrogen-potassium-phosphorus fertilizer. In any case, thereafter at step 110, the combination of plant species, e.g., the combination of the first and second plant species, or alternatively the combination of the first, second and third plant species, are harvested to produce biomass when they are sufficiently mature. Thereafter at step 112, the harvested combination of plant species is processed to produce a bio-fuel. In one embodiment, the harvested combination of plant species is processed at step 112 to produce biomass in the form of the bio-fuel itself. For example, the biomass may be produced at step 112 in any one or more of a solid, a powder and a pellet form that can be burned directly as bio-fuel. Some examples of systems for processing a harvested combination of plant species into a solid, powder and/or pellet form of a burnable bio-fuel are described in co-pending patent application Ser. No. 11/562,643, the disclosure of which is incorporated herein by reference. Any such system may be further modified to include one or more grinding steps/apparatuses, more or fewer mixing steps/apparatuses and/or more or fewer drying steps/apparatuses. For example, it is desirable to maintain the moisture content of the completed and/or partially completed bio-fuel less than a threshold moisture content, e.g., 10% or less, to avoid spontaneous combustion. In an alternative embodiment, in any case, the harvested combination of plant species is processed at step 112 to produce a biomass from which the bio-fuel may be derived according to one or more known processes. In this embodiment, for example, the biomass may be further processed at step 112, using one or more known biomass processing techniques, to produce any of ethanol, bio-diesel fuel, bio-gas, bio-oil, solid bio-fuel, powder bio-fuel and pelletized bio-fuel. Those skilled in the art may recognize other forms of bio-fuel that may be formed or derived from the harvested combination of plant species, and any such other forms of bio-fuel are contemplated by this disclosure.

In one embodiment, the process 100 advances from step 112 to step 114 where the process 100 ends. In an alternate embodiment, the process 100 may loop from step 112 directly to step 108 as shown in FIG. 1 by a corresponding one of the dashed-line arrows. In this embodiment, the steps 108, 110 and 112 may be repeated any number of times, which may be interpreted as planting the first and second (and, in some embodiments, third) plant species in any number of locations during a single growing season, or alternatively as planting the first and second (and, in some embodiments, third) plant species at any single location some number of times, e.g., twice, during a single growing season. In another alternate embodiment, the process 100 may include another optional step 116, and the process 100 may advance in this embodiment from step 112 to step 116 where a substitute plant species may be selected for any one or more of the first, second and third plant species. Following step 116, the process 100 loops back to step 108. In this embodiment, as with the previous embodiment, the steps 108, 110 and 112 may be repeated any number of times, and with each repetition of steps 108, 110 and 112 one or more of the first, second (and, in some embodiments, third) plant species may be replaced with a substitute plant species. Also as with the previous embodiment, the phrase “repeated any number of times” may be interpreted as planting the plant species in any number of locations during a single growing season, or alternatively as planting the plant species at any single location some number of times, e.g., twice, during a single growing season.

Referring now to FIG. 2, a flowchart is shown of one illustrative embodiment of a process for carrying out step 110 of the process 100 of FIG. 1. In the illustrated embodiment, the process of FIG. 2 begins at step 120 where the combination of plant species planted at step 108, i.e., the first and second plant species (and, in some embodiments, the third plant species), is cut at a predefined height above the ground. Illustratively, the predetermined height is selected to minimize dirt spatter on the cut combination of the first and second plant species resulting from rain and/or other watering of the combination of plant species and/or to minimize silicon dioxide on the cut combination of plant species resulting from spattering of dirt from rain and/or other watering, after which the stalk of the plant at least partially grows over the dirt spatter. In any case, it is generally desirable to minimize dirt spatter and/or silicon dioxide on the harvested combination of plant species for a number of reasons. For example, dirt and/or silicon dioxide generally do not burn or does not burn well. As another example, dirt spatter and/or silicon dioxide on the harvested combination of plant species tends to cause the resultant bio-fuel to have higher ash content when burned than would otherwise occur without the dirt spatter and/or silicon dioxide. As yet another example, dirt spatter and/or silicon dioxide on the harvested combination of plant species may cause the resultant bio-fuel to produce more undesirable emissions when burned than would otherwise occur without the dirt spatter and/or silicon dioxide. In any case, the process of FIG. 2 advances from step 120 to step 122 where the cut combination of plant species resulting from step 120 is reduced to smaller pieces. The size of the pieces resulting from step 122 may vary depending upon further processing requirements of the biomass resulting from step 122. From step 122, the process of FIG. 2 returns to the process 100 of FIG. 1.

Example

The following describes one illustrative implementation of the process 100 of FIG. 1 using one example set of plant species. It will be understood that this represents only an example, and that the process 100 may alternatively be carried out generally as described above and using one or more other plant species.

In the illustrative implementation, the first plant species is selected to be Ambrosia trifida, also known as Giant Ragweed, Great Ragweed, Buffalo Ragweed, Bitterweed, Bloodweed, Horse Cane and Tall Ambrosia. Ambrosia trifida is a perennial plant that is native throughout most of North America, and its flowers are pollinated by wind (rather than by insects). The second plant species in this illustrative implementation is selected to be a tall-growing, high-lignin corn species or sorghum species. The tall-growing, high-lignin corn or sorghum species acts in this illustrative implementation as a catalytic crop that forces the Ambrosia trifida to grow taller than when grown alone. Ambrosia trifida, when grown taller as a result of being grown together in competition with a tall-growing, high-lignin corn or sorghum species, generally produces a stalk with greater girth and, consequently, higher lignin content. The selection of Ambrosia trifida and a tall-growing, high-lignin corn or sorghum species thus achieves the bio-fuel production goal of increased crop yield and also the bio-fuel performance goal of increase BTU value (see discussion hereinabove relating to step 102 of the process 100).

It is desirable, although not required, when selecting the corn species as the second plant species, to select a hybrid corn species that is developed to grow without ears, or with ears but with very few, if any, kernels. Kernels have been determined by experiment to be problematic in industrial boiler and burner applications due to slagging at low temperature, and it is therefore desirable to minimize kernel growth in embodiments of the corn species that grow with ears. Corn species that have been grown and tested, and that have been found to have satisfactory BTU and sufficiently low ash include, but are not limited to, “G” family Hybrid Nos. 2G779, 2M746, 2M744, 2M141, 2M748, 2M749, 2J665, 2J668, 2J669, 2D673, 2D653, 2D663 and 2D675, “E” series Hybrid Nos. 2G621, 2G627, 2G628, 2R691, 2R693 and 2R731, and “Tropical Corn” series Hybrid Nos. TMF-2L844 and TMF-2H917, which may be selected for extremely tall growth in warmer climates, all of which are produced by Mycogen Seeds of Indianapolis, Ind., which is a wholly-owned affiliate of Dow AgroSciences, also of Indianapolis, Ind. Sorghum species that have been grown and tested, and that have been found to have satisfactory BTU and sufficiently low ash includes, but should not be limited to, number 1506 hybrid sorghum species which is produced by Mycogen Seeds of Indianapolis, Ind. Further experimental testing revealed that all varieties of tall-growing, high-lignin sorghums did well as a BTU binder and catalyst for the Ambrosia trifida. In this illustrative implementation, the “G” family Hybrid No. 2M748 is selected to grow together in competition with the Ambrosia trifida.

In the illustrative implementation, the ambrosia trifida is supplemented with Ambrosia artemisiifolia, also known as Common Ragweed, Annual Ragweed, Bitterweed, Blackweed, Carrot Weed, Hay Fever Weed, Roman Wormwood, Stammerwort, Stickweed, Tassel Weed, Wild Tansy and American Wormwood. The three plant species, Ambrosia trifida, “G” family Hybrid No. 2M748 corn and Ambrosia artemisiifolia, may be planted together as early as the corn species can be planted in the selected geographical area. Planting of the Ambrosia artemisiifolia is optional as it will generally grow where sunlight permits around the Ambrosia trifida. If overshadowed by corn and Ambrosia trifida, the Ambrosia artemisiifolia seed will generally lie dormant until conditions encourage its growth. The Ambrosia artemisiifolia, in the illustrative implementation, is used as filler for the first year or two that the three plant species are planted in an area where the ambrosia trifida may not initially grow thick enough to block sunlight to the ambrosia artemisiifolia. The Ambrosia trifida is planted among the corn evenly in an interspersed fashion. It is desirable to have more ambrosia trifida plants per acre than the corn, e.g., 75,000-120,000 total plants per acre. This will yield more tonnage per acre than planting more corn plants than Ambrosia trifida. Illustratively, fertilizing should place emphasis on high phosphorus content if and where possible.

In the illustrative implementation, the “G” family Hybrid No. 2M748 corn was planted with a density of 27,000-35,000 seeds per acre. Given adequate fertilizer and sunshine, this hybrid corn species reaches heights of 13-16 feet tall in Northern Indiana. Ambrosia trifida grown together in competition with this corn generally grew 1-3 feet taller with a high-lignin and fibrous stalk. Each Ambrosia trifida plant will generally produce more than 1,000 usable seeds which, due to the high amount of pollen each plant produces, are mostly, if not all, fertile. It has been found that a small field planted with just Ambrosia trifida can produce ample seeds for future needs. The Ambrosia trifida and the “G” family Hybrid No. 2M748 corn (as well as many others of the corn hybrids described above) are both drought resistant. This makes the illustrative implementation of this particular combination of plant species suitable for planting on reclaimed strip mines. Such reclaimed land, while recovered with top soil, has in many cases lost minerals that help retain moisture. It may take 15-20 years for the soil on such land to compact again, and such land generally has difficulty retaining water. The drought resistance of this combination of plant species helps it grow on such reclaimed land despite its porosity. Fertilizing and irrigation, particularly during the first month of growth, will help to ensure adequate crop yields when grown on reclaimed land.

Harvesting the combination of plant species, in this illustrative implementation, generally follows the process illustrated in FIG. 2. Using a precision cutting head, the combination of plant species is cut at a predetermined height above the ground. Illustratively, the cutting head is positioned such that 6-9 inches of stalk are left on the plot of land after the harvest. This minimizes, or at least reduces, dirt spatter and/or silicon dioxide on the harvested combination of plant species as described hereinabove. In any case, the cut combination of plant species is then reduced, e.g., by chopping, into small pieces suitable for further processing of the resulting biomass into one or more bio-fuels.

As described above, growing multiple crops in one growing season may be possible, particularly in warmer climates that have extended growing seasons. In this illustrative implementation, a tall-growing, high-lignin sorghum may replace the corn species in the second growing.

Genetic traits or characteristics may be developed, as described above, to achieve desired growing and/or other goals. In this illustrative implementation, for example, the Ambrosia trifida was developed to have resistance to certain root pests and also resistance to corn borer insects.

Referring now to FIG. 3, a flowchart is shown of another illustrative embodiment of a process 200 for producing a bio-fuel. In the illustrated embodiment, the process 200 begins at step 202 where Ambrosia trifida is planted on one more parcels of land. Illustratively, the Ambrosia trifida may be planted by itself or along with Ambrosia artemisiifolia. In the latter case, the Ambrosia artemisiifolia will grow and thrive in areas that are not yet filled in by the Ambrosia trifida during the first one or more years following the first planting. As the Ambrosia trifida plants become more densely packed in subsequent years they will rob the Ambrosia artemisiifolia of sunlight, and the Ambrosia artemisiifolia will generally become dormant unless and until conditions encourage its growth. The one or more parcels of land may be any parcels of land, including reclaimed mining land and/or other difficult to grow areas as Ambrosia trifida is generally drought resistant.

Following step 202, the process 200 advances to step 204 where additional phosphorus is mixed with a conventional base fertilizer to form a modified fertilizer. In one embodiment, for example, the conventional fertilizer may be a conventional Nitrogen-Phosphorus-Potassium (NPK) fertilizer, although this disclosure contemplates using other conventional fertilizers as the base fertilizer. In any case, the planted Ambrosia trifida is fertilized thereafter at step 206 with the modified fertilizer.

The process 200 advances from step 206 to step 208 where the planted Ambrosia trifida is harvested when it is sufficiently mature. Illustratively, step 208 may be carried out as illustrated in FIG. 2 where the Ambrosia trifida is cut at a predefined height above the ground, and then reduced to smaller pieces. The predetermined height may be selected, for example, to minimize dirt spatter and/or silicon dioxide on the cut stalks of the ambrosia trifida resulting from rain and/or other watering of the crop. The size of the smaller pieces may vary depending upon further processing requirements of the biomass resulting from the harvesting process.

The process 200 advances from step 208 to step 210 where the harvested Ambrosia trifida is processed to produce bio-fuel. In one embodiment, the harvested is Ambrosia trifida is processed at step 210 to produce biomass in the form of the bio-fuel itself. For example, the biomass may be produced at step 210 in any one or more of a solid, a powder and a pellet form that can be burned directly as bio-fuel. Some examples of systems for processing harvested plant species into a solid, powder and/or pellet form of a burnable bio-fuel are described in co-pending patent application Ser. No. 11/562,643, the disclosure of which has been incorporated herein by reference. Such systems may further be modified as described hereinabove. In an alternative embodiment, the harvested Ambrosia trifida is processed at step 210 to produce a biomass from which the bio-fuel may be derived according to one or more known processes. In this embodiment, for example, the biomass may be further processed at step 210, using one or more known biomass processing techniques, to produce any of ethanol, bio-diesel fuel, bio-gas, bio-oil, solid bio-fuel, powdered bio-fuel and pelletized bio-fuel. Those skilled in the art may recognize other forms of bio-fuel that may be formed or derived from the harvested Ambrosia trifida, and any such other forms of bio-fuel are contemplated by this disclosure.

In one embodiment, the process 200 advances from step 210 to step 212 where the process 200 ends. In an alternate embodiment, the process 200 may loop from step 210 back to step 202 as shown in FIG. 3 by a corresponding dashed-line arrow. Alternatively, no additional planting may be necessary and the process 200 may instead loop from step 210 to step 204. In either case, the steps 202-210 or steps 204-210 may be repeated any number of times, which may be interpreted as planting the Ambrosia trifida in any number of locations during a single growing season, or alternatively as planting the Ambrosia trifida at any single or number of locations some number of times, e.g., twice, during a single growing season.

Referring now to FIG. 4, a flowchart is shown of another illustrative embodiment of a process 300 for producing a bio-fuel. In the illustrated embodiment, the process 300 begins at step 302 where two or more plant species are planted, each on a separate parcel of land. The two or more plant species may include, for example, but should not be limited to, any combination of separately planted Ambrosia, e.g., Ambrosia trifida or Ambrosia artemisiifolia, Amaranthus, e.g., Amaranthus rudis, Amaranthus hybridus or Amaranthus retroflexus, any of the corn species described hereinabove, and any of the sorghum species described hereinabove.

Following step 302, the process 300 advances, in one embodiment, to step 304 which is shown in FIG. 4 by a dashed-line box to indicate that some embodiments of the process 300 may include step 304 while others may not. In any case, at step 304 any one or more of the plant species planted at step 302 are fertilized. The fertilization step 304 may occur at any time, and may occur multiple times, while the one or more of the plant species planted at step 302 is/are growing. The fertilizer may be any conventional plant fertilizer, and one specific example fertilizer is a conventional nitrogen-phosphorus-potassium fertilizer which is modified by supplementing this base fertilizer with additional phosphorus.

In any case, the process 300 in the illustrated embodiment advances from step 304, or in embodiments that do not include step 304 the process 300 advances from step 302, to step 306 which is shown in FIG. 4 by a dashed-line box to indicate that some embodiments of the process 300 may include step 306 while others may not. In any case, at step 306 any one or more of the plant species planted at step 302 are treated for insects and/or for other pests. Example treatments may include, for example, but should not be limited to, treatment for root pests, treatment for corn borer insects, treatment for stalk-boring pests, and the like. Like the fertilizing step 304, the treatment step 306 may occur at any time, and may occur multiple times, while the one or more of the plant species planted at step 302 is/are growing.

The process 300 advances from step 306, and from step 304 or 302 in embodiments of the process 300 that do not include step 306, to step 308 where each of the separately planted plant species that were planted at step 302 is harvested when sufficiently mature. It will be understood that step 208 does not require that each of the number of plant species is harvested simultaneously, but rather that each is harvested when each is sufficiently mature. Illustratively, step 308 may be carried out as illustrated in FIG. 2 where each of the plant species is cut at a predefined height above the ground, and then reduced to smaller pieces. The predetermined height may be selected, for example, to minimize dirt spatter and/or silicon dioxide on the cut stalks resulting from rain and/or other watering of the plant species. The size of the smaller pieces may vary depending upon further processing requirements of the biomass resulting from the harvesting process.

The process 300 advances from step 308 to step 310 where the combination of harvested plant species is processed to produce bio-fuel. In one embodiment, the harvested combination of plant species is processed at step 310 to produce biomass in the form of the bio-fuel itself. For example, the biomass may be produced at step 310 in any one or more of a solid, a powder and a pellet form that can be burned directly as bio-fuel. Some examples of systems for processing harvested plant species into a solid, powder and/or pellet form of a burnable bio-fuel are described in co-pending patent application Ser. No. 11/562,643, the disclosure of which has been incorporated herein by reference. Such systems may further be modified as described hereinabove. In an alternative embodiment, the harvested combination of plant species is processed at step 310 to produce a biomass from which the bio-fuel may be derived according to one or more known processes. In this embodiment, for example, the biomass may be further processed at step 310, using one or more known biomass processing techniques, to produce any of ethanol, bio-diesel fuel, bio-gas, bio-oil, solid bio-fuel, powdered bio-fuel and pelletized bio-fuel. Those skilled in the art may recognize other forms of bio-fuel that may be formed or derived from the harvested combination of plant species, and any such other forms of bio-fuel are contemplated by this disclosure.

In one embodiment, the process 300 advances from step 310 to step 312 where the process 300 ends. In an alternate embodiment, the process 300 may loop from step 310 back to step 302 as shown in FIG. 4 by a corresponding dashed-line arrows. Alternatively, no additional planting may be necessary and the process 300 may instead loop from step 310 to step 304. In either case, the steps 302-310 or steps 304-310 may be repeated any number of times, e.g., twice, during a single growing season.

It will be understood that any of the processes 100, 200 and 300 illustrated and described herein may be grown on any type of land. Most, if not all, of the plant species described herein are generally drought resistant, and may accordingly be planted/grown on depleted land such as reclaimed land from strip mining, or in other low plant nutrient land such as bogs or peat bogs. Generally, planting and growing plant species in either of these types of land will benefit from fertilization and, at least in the former case, from irrigation and/or frequent watering. Fertilization may, as described hereinabove, be enhanced by adding phosphorus to a base fertilizer, such as a conventional nitrogen-phosphorus-potassium fertilizer. It will be understood that while at least some of the plant species described herein may be planted/grown on such depleted or other low plant nutrient land, all of the plant species illustrated and described herein may alternatively be planted/grown on other types of land in any geographical location suitable for sustaining plant life, and may be supplied with fertilizer, including phosphorus-enhanced fertilizer. It will further be understood that with any of the processes 100, 200 and 300 illustrated and described herein, it is desirable to maintain the moisture content of the completed and/or partially completed bio-fuel less than a threshold moisture content, e.g., 10% or less, to avoid spontaneous combustion, as described hereinabove.

While the invention has been illustrated and described in detail in the foregoing drawings and description, the same is to be considered as illustrative and not restrictive in character, it being understood that only one illustrative embodiment thereof has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected. For example, one or more other plant species may be substituted for Ambrosia trifida in either of the processes 100 and 200 illustrated and described herein. One example substitute plant species includes, but is not limited to, one or more species of amaranth, i.e., Amaranthus. Specific examples include Amaranthus rudis, also known as tall Amaranthus and common waterhemp, Amaranthus hybridus, also known as smooth Amaranthus, pigweed and red Amaranthus, and Amaranthus retroflexus, also known as red-root Amaranthus, redroot pigweed and common Amaranthus. As another example, various other combinations of plant species may be used in the processes 100 or 300 illustrated herein. As a specific example, the first plant species in either embodiment may be Amaranthus, e.g., Amaranthus rudis, Amaranthus hybridus and/or Amaranthus retroflexus, and the second plant species may be Ambrosia, e.g., Ambrosia trifida and/or Ambrosia artemisiifolia, or a corn species or a sorghum species. Alternatively, the first plant species may be Ambrosia, e.g., Ambrosia trifida and/or Ambrosia artemisiifolia, and the second plant species may be Amaranthus, e.g., Amaranthus rudis, Amaranthus hybridus and/or Amaranthus retroflexus. 

1. A method for producing a bio-fuel comprising: selecting a first and a second plant species such that the second plant species, when grown together in competition with the first plant species, causes a BTU value of the first plant species to increase above a range of BTU values that the first plant species has when grown alone, planting a combination of the first and second plant species together in competition, harvesting the combination of the first and second plant species when sufficiently mature, and processing the harvested combination of the first and second plant species to produce the bio-fuel.
 2. The method of claim 1 wherein the first plant species has a lignin content, and wherein the second plant species causes the BTU value of the first plant species to increase by causing the first plant species to grow with greater lignin content than when grown alone.
 3. The method of claim 2 wherein the lignin content of the first plant species varies as a function of a size of the first plant species, and wherein the second plant species is a catalytic plant species that, when grown together in competition with the first plant species, causes the first plant species to grow larger than when grown alone so that the lignin content of the first plant species correspondingly increases.
 4. The method of claim 3 wherein the first plant species is ambrosia trifida.
 5. The method of claim 4 wherein the second plant species is a tall-growing, high-lignin one or a combination of a corn species and a sorghum species.
 6. The method of claim 5 wherein the second plant species is one or a combination of a G family, an E series and a tropical corn series hybrid corn species and a number 1506 hybrid sorghum species.
 7. The method of claim 5 wherein planting a combination of the first and second plant species further comprises planting ambrosia artemisiifolia along with the first and second plant species such that a resulting combination comprises ambrosia trifida, a tall-growing, high-lignin one or a combination of a corn species and a sorghum species and ambrosia artemisiifolia, and wherein harvesting comprises harvesting the resulting combination when sufficiently mature.
 8. The method of claim 5 further comprising carrying out the selecting, the planting and the harvesting events at least twice in a single growing season.
 9. The method of claim 8 wherein the second plant species for a first one of the selecting, the growing and the harvesting events is the tall-growing, high-lignin corn species, and wherein the second plant species for a second one of the selecting, the growing and the harvesting events is the tall-growing, high-lignin sorghum species.
 10. The method of claim 1 further comprising selecting the second plant species to have a BTU value that is within a predefined range of BTU values.
 11. The method of claim 10 wherein the predefined range of BTU values is greater than or equal to the range of BTU values of the first plant species.
 12. The method of claim 1 further comprising selecting either of the first and second plant species to have resistance to root pests.
 13. The method of claim 1 further comprising selecting either of the first and second plant species to have resistance to at least one of corn borer insects and stalk-boring insects.
 14. The method of claim 1 wherein harvesting comprises cutting the combination of the first and second plant species at a predetermined height above the ground, the predetermined height being selected to minimize at least one of dirt spatter and silicon dioxide on the cut combination of the first and second plant species.
 15. The method of claim 14 wherein harvesting further comprises reducing the cut combination of the first and second plant species to smaller pieces.
 16. The method of claim 1 wherein planting a combination of the first and second plant species further comprises planting a third plant species along with the first and second plant species such that a resulting combination comprises the first, second and third plant species, the third plant species being selected to at least temporarily supplement one of the first and second plant species, and wherein harvesting comprises harvesting the resulting combination when sufficiently mature.
 17. The method of claim 1 wherein processing comprises processing the harvested combination to produce the bio-fuel in any of a solid, a powder and a pellet form.
 18. The method of claim 1 wherein processing comprises: processing the harvested combination to produce a bio-mass, and processing the bio-mass to produce any of ethanol, bio-diesel fuel, bio-gas, bio-oil, solid bio-fuel, powdered bio-fuel and pelletized bio-fuel.
 19. The method of claim 4 further comprising: mixing additional phosphorus with a base fertilizer to form a modified fertilizer, and fertilizing the planted ambrosia trifida with the modified fertilizer.
 20. The method of claim 19 wherein the base fertilizer is a nitrogen-phosphorus-potassium fertilizer.
 21. The method of claim 19 wherein the second plant species is ambrosia artemisiifolia.
 22. The method of claim 1 wherein the first plant species is a species of Amaranthus.
 23. The method of claim 22 wherein the species of Amaranthus comprises Amaranthus rudis.
 24. The method of claim 22 wherein the species of Amaranthus comprises Amaranthus hybridus.
 25. The method of claim 22 wherein the species of Amaranthus comprises Amaranthus retroflexus.
 26. The method of claim 22 further comprising: mixing additional phosphorus with a base fertilizer to form a modified fertilizer, and fertilizing the species of Amaranthus with the modified fertilizer.
 27. The method of claim 26 wherein the base fertilizer is a nitrogen-phosphorus-potassium fertilizer.
 28. The method of claim 22 wherein the second plant species comprises at least one of Ambrosia trifida and Ambrosia artemisiifolia.
 29. The method of claim 22 wherein the second plant species comprises at least one of a corn species and a sorghum species. 